1. Field of the Invention.
P-type GaN is a valuable electronic material. This invention relates in general to a method for growing a semiconductor material, and more particularly to a method for growing p-type GaN.
2. Description of Related Art.
In the field of electronics, new materials are being used to perform previously unobtainable goals, e.g., new devices, smaller devices, and more efficient devices. The ability to grow or otherwise manufacture these new materials has been limited by the understanding of the chemistry that is occurring, the need for the finished devices, and the ability to mass produce such devices.
The devices result from different areas of study. The first area is the ability to actually grow the material onto a substrate. Several different types of growth techniques have been approached for various materials. The second area is the ability to process those materials once they are grown onto a substrate. Many materials that are now in their infancy take their growth and processing techniques from more established materials, e.g., silicon, gallium arsenide, and others.
The Group III (Al, Ga, In) nitrides are materials that are producing devices previously unavailable in the electronics market. The alloy system (Al, Ga, In)N allows the fabrication of semiconductor materials thatemit light in the wavelength range from 200 to 700 nm, covering the entire range of visible light. These diodes cannot be made with any other materials currently known.
These advances in the ability of a material to produce luminescence in those optical regions allow for the use of the electronics to take the place of typical lighting fixtures. Further, the use of blue and UV diodes in the recording industry for the recording of CD-ROMs instead of the red/infared lasers (800 nm) currently being used in that industry allow for a up to four times higher density of information per unit distance on a CD-ROM track. Production of Light Emitting Diodes (LEDs) which use a lens shaped protective cover allow for high intensity light at low power levels.
However, gallium nitride films are hard to grow and process. Further, doped gallium nitride, especially gallium nitride that is doped with a p-type dopant, requires post-growth processing to achieve acceptable levels of active dopant atoms within the crystalline structure. The post-growth processing damages the gallium nitride crystalline structure and thereby degrades the overall properties of the material.
It can seen then that there is a need for producing gallium nitride films with better overall properties. It can also be seen that there is a need for producing gallium nitride films with p-type dopants that do not require post-growth processes. It can also be seen that there is a need for producing gallium nitride films at a lower cost.